All About… Potatoes

ALL ABOUT POTATOES

Potatoes are one of the most controversial foods within the Paleo community. The purists would insist that Potatoes are categorically NOT Paleo (for why, see “The Hunter-Gatherer Diet Debate” below) and yet there is much to commend the Potato. Chief amongst this is the fact that Potatoes are relatively useful sources of carbohydrates and they also have a host of vitamins. On the ‘nutrient vs. anti-nutrient’ scale they certainly don’t fare badly, and when analysed for the observable interaction with human physiology they actually seem like a relatively ‘healthy’ foodstuff. This is the reason why many Modern Paleo advocates will include some Potatoes in their diet.

They may be absolutely right, but the humble Potato is not as benign as it might seem either. This article explains the Potato controversy and will help you to understand why there is conflict over this modern Western dietary staple.

But first:

The Hunter-Gatherer Diet Debate

We do NOT find that Palaeolithic man, or hunter-gatherers, or ancient tribes etc. consumed Potatoes. Judging by studies of the evolution of crops, Potatoes are, relatively speaking, a fairly ‘new’ foodstuff. They require both cultivation and harvesting and are a food that began to thrive come the time of agriculture. Additionally, Potatoes are poisonous and toxic when eaten raw so have to be cooked in order to render them digestible. This means hunter-gatherers would not have consumed Potatoes – and hence the die-hard Paleo fanatics (who are anthropologically and ideologically minded) maintain that anyone following the Paleo diet should not include the Potato.

The Modern Paleo Potato

The issue that we at Paleo in the UK have with Paleo Purists is that following an ideological ethos of recreating a true representation of a caveman diet suggests that we don’t think human beings have evolved at all in conjunction with their environment. This is patently false. The advent of cooking changed our food consumption, with the human digestive system and microbiome following suit, providing for an accompanying evolution of consciousness and intellectual capacity. We are not interested in maintaining that we are primates and should live entirely ‘ancestrally’. We are devoted to analysing how far our digestion really has evolved alongside our food supply.

Have we, therefore, evolved to digest the ubiquitous Potato? Perhaps.

But does the Potato have a robust enough nutrient profile – and does it have any potential anti-nutrients which we need to consider?

Of note here is that Potatoes are an eliminated food the moment that you consider an Autoimmune Paleo protocol. This indicates that there is something in the Potato which can be triggering in some way to the immune system which sparks inflammation. And there is – Potatoes are a nightshade vegetable. All nightshades are eliminated when following an Autoimmune Paleo Protocol – and for all about why, read our Nightshade page here.

For some, Potatoes are the best tolerated nightshade, for others they are the worst-tolerated. But beyond the fact that they are nightshade (again, all the details about why this is a big deal can be found on the All About Nightshades page) there are other issues which make Potatoes a potentially immune triggering and inflammatory – and therefore eliminated – food.

Potatoes are Carbohydrates

Despite what you may think, Potatoes are not eliminated because they are carbohydrate-rich: remember, the Paleo diet is not prescriptive about macronutrient ratios. Whilst you can personalise a Paleo template to resemble any macronutrient split you choose, Paleo is not intended to be (and most likely, for scores of truly ancestral tribes, was not ever) ‘low-carb’.

But we mention the ‘carb’ thing because there are many articles out there which suggest that the Potato is a simple source of starch, and as such, consuming Potatoes is akin to simply eating table sugar.

This is blatantly false – and in fact, Potatoes contain much more nutrition than you might imagine.

Potatoes are full of B6, Vitamin C, Potassium, Copper, Magnesium and a fair sprinkling of antioxidants. These come in a nice starchy package which would perhaps be counter to your goals if you are attempting to lose or regulate weight but which in no way makes Potatoes an unhealthy food.

There are also myths about the Glycaemic Index or the Glycaemic Load value of Potatoes, the suggestion being that Potatoes spike blood glucose and therefore insulin incredibly after the consumption.

The more we study the glycaemic scores of foods, the more we realise that in no way is this a universal science. All carbohydrates’ glycaemic impacts vary according to what they are consumed with – and the individual carbohydrate tolerance of the person consuming the foods. This is not as simple as stating that eating carbohydrate sources (such as Potatoes) with a bit of fat (like butter) will blunt the glucose/insulin response. Latest research proves this to be, at best, an oversimplification and, at worst, an erroneous assumption. The more we study blood sugar and insulin responses the more we realise that the only thing we can guarantee is that each individuals’ blood glucose release on the consumption of any carbohydrate varies widely – and not just to the responses of other people. The same person can have completely different blood glucose responses to the same food, simply consumed at different times. Everything from stress to sleepless nights can affect insulin responses – and the microbiome can also have a dramatic effect.

This last comment is interesting because for some time now Potato starch has been linked to improvements in the gut microbiome, feeding the bacterial population to support positive health outcomes. There is controversy about this too, however.

The one conclusion that we can make about the carbohydrate load of a Potato is that there are worse foods out there. Consumed with the skins there is a good deal of fibre and vitamin and mineral rich sustenance. They are also easy to cook, digest and make really tasty. This is why many people who have traversed through their early Paleo journey have chosen to reintroduce the Potato, with success.

The Potato Dark Side

The ‘problem’ with Potatoes is all to do with the glycoalkaloids Potatoes contain. Glycoalkaloids are the chemical compounds which are part of the problem behind Nightshades for anyone with autoimmune conditions.

Glycoalkaloids are compounds that allow water and oil to mix. As far as biochemistry goes, this is a very useful function for the potato, but within the human body the mixing of oil and water can actually allow for entrance of the glycoalkaloid into the membranes of cells in order to restructure them.

Glycoalkaloids can theoretically do this restructuring cell damage to the membranes of cells that line the intestinal tract. This is part of the reason why Nightshades are eliminated on an Autoimmune diet and for conditions in which Intestinal Permeability and/or impairment of the lining of the GI tract is suspected. Any substance which can further change or damage the cells of the gut wall is not recommended for consumption when following any healing protocol.

But we must issue one massive word of caution. Glycoalkaloids are a HUGE family of chemicals.

Several, though by no means all, are potentially toxic in the way described above. Their toxicity depends upon the precise action of the specific glycoalkaloid in question, and the terrain into which they are travelling – i.e. the integrity and health of the gut to begin with.

The health and integrity of the gut and the overall wellbeing of each individual will be the main factor in whether potatoes are going to be “Healthful Nutrition” for them.

To complicate matters, the glycoalkaloid content varies within each different Potato variety (and probably in each individual potato for that matter). Glycoalkaloids are held in the skin of potatoes meaning that in some cases removal of the skin can dramatically lower the overall glycoalkaloid content. The only problem with this is that the bulk of the nutrients mentioned above as ‘healthful’ parts of the Potato are also held in the skin – meaning that removing the skin removes the bulk of what made the Potato ‘good’, not just what makes it ‘bad’.

We do just want to mention that glycoalkaloids are present in many foods – beyond Potatoes and even beyond the nightshade family. This includes blueberries, huckleberries, okra, apples, cherries, sugar beets and artichokes. As with absolutely everything (especially when considering foods based on the presence of anti-nutrients, rather than because of an allergy) the dose is very important. We mention glycoalkaloids in the context of potatoes because levels are higher and these have been better studied. Beyond this, the glycoalkaloid content of the foods in the list above are well within safe limits for consumption, regardless of what you may read on some scaremongering sites on the internet.

Picking Your Potato

A final consideration about Potatoes is that we do not just consume them as Potatoes but we also buy chips, crips and all manner of processed potato-based foodstuffs. Whilst none of these ‘processed’ foods might enter on the Paleo dinner table, it is of interest that most commercial Potato products are made from a breed of Potato called the Snowden variety.

Snowden potatoes are grown almost solely for the crisp market (or ‘potato chip’ market in the US) and they are NOT sold as ‘potatoes’ that you can buy loose in shops. However, Snowden Potatoes have been shown in tests to contain the highest level of glycoalkaloids – within the potato flesh itself – of all Potatoes. This means that processed crisps are likely to be much higher in glycoalkaloid content than a Potato that you buy to eat and/or make Potato products yourself.

The last note on glycoalkaloid vs. nutrient content of Potatoes is that storage matters to the development of glycoalkaloids within the Potato – with cool, dry and dark being best to keep toxicity low.

So if you want to try Potatoes on your Paleo diet (remember NOT AIP) then the best thing to do is to make sure that you have a bedrock of good health and digestive robustness first. We’d obviously recommend spending some time potentially leaving out the Potato if you are in any doubt whatsoever about whether you tolerate them well. When you do decide to put Potatoes into your diet there are a few guildelines:

The richer the Potatoes’ skin colour (pink, purple, russet, heirloom etc.), the higher the content of vitamins and minerals encased within the potato itself. This means that you will be getting even more ‘goodness’, or nutrient-density, which is a key tenet of a Paleo lifestyle.

The second thing to note is that organic and local will always be best when it comes to vegetables. The reason for this is because vegetables, including Potatoes, are mostly water – and this water is brought into the crop from the ground. Along with the water comes the nutrients and minerals and/or any ‘nasties’ that are contained within the soil. Organic soil may or may not contain more nutrients – this will depend entirely on the fertiliser and crop rotation practices of the farm in question. However, an organic Potato will NOT contain any of the pesticides, toxins or other chemicals used in non-organic farming. This means that your Potato will be much lower in the anti-nutrients (in this case, non-plant toxins) that you are trying to avoid.

And finally… Cooking your Potato…

Boiling, baking and even boiling/mashing Potatoes are all perfect ways to consume them. The one thing we would caution against is the fats you choose to cook your Potatoes in – whether that’s to roast, bake or fry. Fat quality is of utmost importance (we will be writing about this in due course in our “Deeper Science” section) and any old fats, hydrogenated oils, rancid fats or fats which are overheated (to their ‘smoke point’ and over) are going to become toxic. Fats can be ‘oxidised’ – which basically means ‘spoilt’, and oxidised fats have serious consequences in terms of inflammatory potential within the human body. For more on this for now, an excellent read is “Deep Nutrition” – the author of which has pegged the consumption of oxidised and damaged fats as worse for the human body than smoking a cigarette.

Extreme claims, yes – but not something worth ignoring, particularly when it is perfectly possible to make chips WITHOUT using oils that are already damaged prior to leaving the supermarket (any plant oil or vegetable oil that is hydrogenated, in a clear bottle). We recommend oven baking chips and roast potatoes in animal fats such as lard/tallow/goose fat/duck fat – and don’t let the oil get to the point of smoking where you can smell the fats oxidising.

Following the above principles, Potatoes may not only be a source of nutrients but also a familiar source of comfort. They can also make some of the British comfort-food recipes you might miss on a Paleo diet possible – from cottage and shepherd’s pies to hotpots and stews.

For more on the Nightshade family, from which the potato comes – do check out our All About Nightshades page.

References:

Friedman, M., Potato glycoalkaloids and metabolites: roles in the plant and in the diet, J Agric Food Chem. 2006;54(23):8655-81

Gee. J. M., et al., Effects of saponins and glycoalkaloids on the permeability and viability of mammalian intestinal cells and on the integrity of tissue preparations in vitro, Toxicol In Vitro. 1992;10(2):117-128